Step and repeat machine



July 23, 1968 c. R. JOHNSON 4 STEP AND REPEAT MACHINE Filed July 16, 1965 2 Sheets-Sheet 1 CHAR; 5 I? .Jmwsaw INVENTOR.

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July 23, 1968 c. R. JOHNSON STEP AND REPEAT MACHINE 9 4 $2 k 5 \re 70 fig 4 CHAR; s: A? bx/Also INVENTOR.

United States Patent Office 3,3Q3fi24 Patented July 23, 1968 3,393,624 4 STEP AND REPEAT MACHINE Charles R. Johnson, Floyd Knobs, Ind., assignor t Zenith Engraving Company, Louisville, Ky.

Filed July 16, 1965, Ser. No. 472,485 8 Claims. (Cl. 95-73) ABSTRACT OF THE DISCLOSURE A step and repeat machine consisting of a base frame on which a film of image receptive material is mounted. An image carrier is mounted to move over the base. The image carrier has a device for positioning images in predetermined positions thereon and apparatus for securing the image carrier in each selected position. The base member has parallel channels in which there are movable pins used for positioning the image carrier. At the end of each channel there are fixed reference pins. There are spring drawn curtains connected to the image carrier for masking the unexposed film.

This invention relates to a step and repeat device for reproducing an image successively on different portions of a sheet of image receptive material such as a film or printing plates or the like. More specifically, the invention relates to a step and repeat machine which is particularly adapted to position a means carrying an image adjacent different portions of a sheet of unexposed photographic film in succession and to expose the different portions of said film sheet in succession whereby to provide a plurality of like reproductions of the image thereon.

It is an object of the present invention to provide an image reproducing machine of the type referred to wherein movement of an image carrying means from one position to another adjacent a sheet of image receptive material may be accompanied readily and with a high degree of accuracy, and wherein operable means are provided for maintaining the image carrying means in engagement with or closely spaced relationship with portions of the sheet of image receptive material during reproduction of the image thereon and for maintaining said image carrying means a suitable distance from the said sheet of image receptive material during movement of said means relative thereto.

Still a further object of this invention is to describe a step and repeat machine that is rugged, inexpensive and stable, requiring a minimum of adjustment to account for wear.

These and other objects of this invention are attained in one embodiment of the invention by providing a step and repeat machine consisting of a base frame on which is mounted a film of image receptive material, an image carrier mounted to move over the film supporting base, the image carrier having means for positioning images in predetermined positions thereon and means for securing the image carrying means in each selected position.

Still a further object of this invention is to describe a step and repeat machine wherein devices are provided for continuing a relationship of image or images as set up in the negative layout or stripping operation common to the trade.

Still a further object of this invention is to describe a step and repeat machine wherein devices are provided for positioning an image receptive material or surface in a repeatable position in the machine so as to set up a continuing relationship of image or images in the step and repeat machine with continuity or relationship extending from the negative layout operation to the step and repeat H machine and to the so positioned image receptive surface.

Still a further object of this machine is to describe a step and repeat machine wherein rapid and precise movement of a single image may be accomplished in the almost total darkness of a darkroom through the location of predetermined openings over predetermined pin positions.

Other objects and advantages of this invention become apparent in the following detailed description. When read with references to the accompanying drawings like numbers refer to like parts and in which:

FIGURE 1 is a plane view of the machine with parts broken away;

FIGURE 2 is a sectional view on line 2-2 of FIG- URE 1;

FIGURE 3 is a view taken on line 3-3 of FIGURE 1;

FIGURE 4 is a bottom plan view of the image carrier or chase;

FIGURE 5 is a view of a punched strip to be used in conjunction and connection with both the chase for providing location of image carrying material on the chase and also for positioning a chase in a sequence of relationships to sensitized surface of film or plate.

FIGURE 6 is a view of machined pin to be used with strip shown in FIGURE 5; and

FIGURE 7 is an enlarged sectional view taken on line 7-7 of FIGURE 1.

The basic purpose of this invention is to provide a machine for stepping multiple images on film. It is usable on offset plates and can be used on step and repeat photomechanically sensitive surfaces. The need in the printing art is to take one negative and move it in a vertical and horizontal direction with a flexibility of determining each dimension and with accuracy in setting the dimensions.

The control of position and movement is based on pin register counter. The positioning of image receiving material-sensitized material-is on an elastic material such as rubber or the like.

In preparation, two or more dimensionally stable strips are punched with distance between the punched holes representing the dimension between the steps either vertically and/or horizontally. Pins machined to proper dimension are inserted in channels which are parallel to the rubber support for the image receiving material and parallel to each other. A channel is positioned on opposite sides of the rubber support. The movable pins are located in the channels by inserting where the holes in the punched strip fall. The strips remain over the pins and hold them in proper position. The pins are so designed that a fiat head with diameter greater than the pin is held securely within the channel to maintain constant and secure position within channel. The strips have a hole in each end thereof which are placed over pins which are permanently fixed in exact relationship to each channel. The fixed zero pins are the index on which the image receiving surface-the sensitized material-is related and from which the dimension of the step is based.

The control of the pin positions in the chase is accomplished by a punched dimensionally stable strip of material usually taped to the chase and removable machined pins. The image carrying material after being properly positioned is held in this position by being taped to the chase.

Although the present invention is not so limited, the step and repeat machine which constitutes the presently preferred embodiment thereof is particularly adapted to reproduce an image successively on different portions of a sheet of photographic film. The sheets of film with a plurality of like reproductions of an image thereon which are provided by the machine are useful for a variety of purposes and find particularly utility in the printing and allied fields. Printing plates or the like made from the film sheets can be used to produce a number of image reproductions simultaneously and thus printing operations may be accelerated.

In accordance with the present invention, there is provided a base having a flat upwardly exposed surface on which is secured a rubber member 12 for supporting a sheet of image receptive material, it being understood that material other than rubber may be used as long as it has similar properties. Around the member 12 and spaced therefrom is rubber member 14. This member 14 extends slightly above the top of member 12 as is shown in FIGURE 2. The space 16 between members 12 and 14 is used Where vacuum means (not shown) is employed to hold the image receptive material in desired position, it being understood that the use of vacuum may be omitted in some embodiments of the invention.

The base 10 is provided with extending tabs or ears 18 and 20 which support a pair of spring drawn curtains 22 and 24 for the purpose of covering or masking of the film or image receptive material that is not to be exposed, it being understood that a source of light (not shown) either mounted on the chase or separated there from is employed in making exposures in a manner as is well understood in the art. The free ends of the curtains 22 and 24 have a fastening bar 26 secured to each curtain. The bars have a series of openings 27 which are adapted to receive screw thread posts mounted on the chase. The curtains are secured to bars 26 by means of slat 28 by suitable screw means as shown in FIGURE 3. A rubber strip 30 carried by bars 26 light seals the curtain to the chase.

A pair of parallel channels 32 and 34 are secured on the upper surface of the base 16. These channels are open at one end. Pins 36 shown clearly in FIGURES 1 and 2 are removably carried in the channels.

Adjacent the closed end of each channel is fixed pin 46 which is termed the zero pin. At the open end of each channel may be and preferably are located fixed pins 42. Dimensionally stable strips 44 punched in predetermined positions are placed over the channels and the movable pins 36 are positioned to extend through opening punched in the strips 44. The openings at one end of the strips are placed over pin 40. The openings at each end of the strips provide exact location and position of strips with the various sequence of openings in the strips positioned thusly. If pins 42 are not used the strips 34 are taped to the top of the channels.

In FIGURE 1 the strip 44 is broken away in part to show the shape of the channel and the movable pins 36. It is preferred that pins 36 be placed in the base 10 beyond the edge of the rubber members 12 and 14. If the pins are employed the punched or tabbed film is placed thereon. This positions the film in the proper location. Thereafter the film is then taped in place of rubber member 12.

The chase generally shown at 45 includes a clear window 48 or transparent plate carried by frame 50 and disposed of in use in a plane parallel to the plane of member 12. The frame 50 has extensions 52 extending therefrom. These extensions are provided with machined opening 54 for the reception of pins 36. When the openings are in place on the pins the longitudinal edges of the frame 50 are at right angles to the channels. To opposed longitudinal edges of chase frame 50 is provided a series of screw threaded studs 53 'with mating members 55 which are tightened to secure the roller curtains to the chase.

The under side of the chase frame in arm 53 has pin opening 56 for the reception of a removable pin. In line with pin opening 56 and extending parallel to the longitudinal edge of the frame '50 is groove 58. The strip 60 shown in FIGURE 5 is punched with holes 62, 63, 64, etc. The number of holes in strip 60 depends on the dimension of the step and the number of steps required. The image carrying material will be punched or tabbed so as to be placed over pins in the hole 56 and groove 58. It is to be understood that arm 51 of chase frame may be provided with similar arrangement of pin and groove as shown in arm 53.

The strip 60 is taped to the chase with opening 62 in line with opening 56, and the other openings 63, 64 and any other opening falls over groove 58. Removable pins similar to pin 66 are placed in opening 63, etc. and extend into the groove 58. The opening in the image carrying material is placed over two or more of the pins 66. This aligns the image in proper position on the chase window 48. The image carrying material is now taped to the chase window and the pins 66 are removed. That part of Window 48 not occupied by the image carrying material is masked to prevent the image receiving material from being exposed only to desired extent. The movement of the image carrying material in successive positions over strip 60 is accomplished by positioning openings in image carrying material over pins positioned in successive openings in strip '60.

The chase is provided with bars 68 with pins 70 fixed to extend through these bars. The bars 68 are adapted to rest on the base 10 between the channels 34 and the sealing strip 14. The pins 70 extend through the chase frame 50 or extensions thereof. Secured to the chase frame 50 are handle supports 72. Cam-like members 74 are mounted on shaft 76, which are carried by handle supports 72. Secured to the cams '74 by suitable means such as screws 78 are handle '80. In FIGURES l and 2 one handle is shown in the raised position while the other handle is in the lowered position. The openings 54 in the extensions 52 are positioned over pins 40 and settle by gravity on the pins. When the light has exposed the image to the image receptive material the handles 80 of the chase are raised and the upward camming of the chase through the operation of the cams 74 and pins 70 occurs. The chase is then stepped to one set of pins 36. The stepping up continues for each additional image desired on the one film. The curtains 22 and 24 being removably secured to the chase move therewith.

When proper exposure is made at each position to a light, for example a fixed light on the chase or a removable light associated with the chase, the remainder of the sensitized film, plate or the like is masked by curtains, it being understood that after each exposure and during shifting from one position to the next, the light will be shut off.

While the step and repeat machine described above is particularly adopted for use in transferring images from sections of film or the like to sheets of unexposed photographic film, it will be apparent that the said machine may be readily adapted for other image transferring processes.

What is claimed is:

1. A machine for reproducing an image successively on different portions of a sheet of photographic film comprising a base member having a flat upwardly exposed surface for supporting a sheet of unexposed film, a pair of channels parallel to two sides of the base member and parallel to each other, the said channels having one closed end, movable pins in each channel, a fixed pin adjacent the closed end of each channel, prepunched strips of dimensionally stable material having one opening over each fixed pin and another opening over each movable pin, a chase having a frame with openings for fitting over the fixed and movable pins as the chase is moved over the sheet of unexposed film, a clear plate of translucent material secured to the chase frame, the chase frame having on one frame member on the side adjacent the unexposed film on the base member an opening for a removable pin and a groove for receiving the end of other removable pins, a strip of prepunched material taped to the chase frame over said opening and groove, the chase frame having handles pivotally mounted in handle supports, handle supporting members, a cam-like member carried by the handles, bars resting on the said base member, stud-like members adjacent the ends of said bars, said stud-like members extending through the chase frame, the cam-like members raising the chase frame upon raising the said handles.

2. In a printing apparatus of the character set forth, a base member, means thereon for retaining an unexposed film, parallel channels on two opposed sides of the means for retaining the unexposed film, movable pins in each channel, a prepunched strip secured over each channel with the movable pins extending through the prepunched strips, a chase frame, a clear plate mounted in the chase frame, one member of the frame having an opening for a removable pin and groove for receiving movable pins, a prepunched strip secured to the frame member over the opening and groove, bars carried by the chase frame and resting on the base member adjacent the channels, studs in the bars and extending through the chase frame, handle supports attached to the chase frame on each side of each stud, handles pivotally secured to the handle supports, cam-like members attached to the handles and cooperating with the studs to raise upwardly the chase frame on raising the handles.

3. In a printing apparatus of the character described, a base member, a chase member movable thereover, means on the base for holding movable pins, fixed pin on the base adjacent one end of the means for holding movable pins, prepunched substantially dimensionally stable strips secured over the means for holding movable pins, the said chase having a frame with opening therein to receive the end of the movable pins, a translucent plate mounted in the chase frame, means for positioning an image on the translucent plate in a predetermined position, bars resting on the base member, studs attached to the bars and extending through opening in chase frame, handle supports attached to the chase frame and positioned adjacent the studs, handles pivotally mounted on the handle supports, cam-like members carried by the handles and cooperating with the studs to raise the chase frame from the movable pin upon raising the handles.

4. The device as defined in claim 3 in which the means for holding the movable pins are parallel channels having an open end for each channel.

5. The device as defined in claim 3 in which the means for holding prepunched strip over the means for holding movable pins are fixed pins in the base member.

6. The printing apparatus of claim 2 in which the means for retaining an unexposed film is a rubber member secured to the base member.

7. The device as defined in claim 3 in which the means for positioning an image on translucent plate is a prepunched strip of substantially dimensional material and removable pins for passing through the prepunched strip and into openings in the chase frame.

8. In a step and repeat machine for reproducing an image successively on different portions of a sheet of photographic film comprising a base member, a chase movable over the base member, parallel channels on the base member, movable pins in the channels, fixed pins adjacent the ends of the channels, spring drawn curtains associated with the base member and the chase for masking the unexposed film on the base member, a clear plate carried by the chase for receiving an image, means for locking the chase in position during exposure, and means for camming upward the chase to move the chase carrying image to a new position over the unexposed film, said means for camming upwardly of the chase includes bars resting on the base member, studs fixed to the bars and passing through openings in the chase, pivotally mounted handles and cam-like members carried by the handles and contacting the studs upon raising of the handles. 

